Spartina is a group of grasses that dominates communities of salt marshes in many coastal areas. Many of the insects, snails, birds, mice, and other animals found in these communities rely on Spartina for food, nest building materials, protection for their young, etc. The roots of Spartina also form dense mats that hold together soil in these ecosystems. Many species that live in Spartina salt marshes cannot survive outside of these unique ecosystems. Because living near the ocean is desirable to many humans, many Spartina marshes have been drained & cleared for human development. Analysis of the destruction that came when Hurricane Katrina hit Louisiana in 2005, however, showed that the reduction of salt marshes in coastal Louisiana was a contributing factor to the storm surge penetrating further inland. 1. The value of Spartina salt marshes in protecting coastal areas from storm surge would be classified as which type?
A. Extrinsic.
B. Intrinsic.
C. Neither.
2. The value of Spartina salt marshes in holding soil together would be classified as which type?
A. Extrinsic.
B. Intrinsic.
C. Neither.
3. In general, you would expect species that only live in Spartina salt marshes to have a higher extinction risk than species that can survive in urban areas.
A. True
B. False
4. Based only on the information included in this scenario, extinction risk for species that only live in Spartina salt marshes would be most influenced by which factor?
A. Restricted geographic range.
B. Narrow habitat requirements.
C. Small population size.